Recommendations for Calcium deficiency - Coco

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ttystikk

ttystikk

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Something that directly affects nutrient takeup and is so often ignored I just suggest starting there; humidity. If your humidity levels changed (and as seasons change it is very likely to change the RH in your room) that could be a cause of your Ca problems.

Low humidity levels force plants to take up more moisture to compensate, which is why you run low values for nutes in dry climates. The opposite is also true and is easier to miss; when humidity climbs, your EC should climb with it, even as high as 2.4 with high humidity levels of 65% or more. When humidity climbs and EC doesn't, the plant will start to starve for nutes because it isn't bringing enough up with the water it's transpiring.

Ca is one of the worst offenders with this, because it's immobile and the affected leaves will not recover if all you do is change the nutes your roots see. Seamaiden's suggestion to foliar feed immobile nutrients is wise for this reason. When I sealed my room and could maintain humidity levels above 20% (!), I noticed my girls needed higher EC- and when they got it they really took off! To be specific, I added 5ml/gal of cal-mag in the dry, and 10 after the room was sealed. This was on top of whatever Ca the nutes had already. I'm in 50/50 coco/hydroton mix.
 
BCrocker

BCrocker

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check your bottles and be sure they are transparent as applejuice. If they are cloudy at all they are bad.. Shake it up good and pour some out. It should be clear with nothing floating around.
My CalMG+ is cloudy and kind of nasty looking. I have another bottle unopened, I'll check it out.
 
BCrocker

BCrocker

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First thought is that it's really refreshing to see someone who actually knows what a Ca- looks like. That's my first thought.

Second thoughts are as follows: Get a separate Ca and Mg product. I like BioLink's 6% Ca, it's certified organic and doesn't give you extra N. Once I separated out Ca and Mg, I found everything went that much easier. Incorporating worm castings into the mix, as teas, top-dressings or part of your coir mix are quite helpful here as well, as can be good old molasses (it's part of my feeding regimen from start til end).

Allow pH to range a little more broadly, I feel that 5.8 is a bit tight and you'll see better uptake if you allow a range, easily up to 6.2, and ranges outside both ends, high and low, are also acceptable.

You will not observe any improvement in the already-affected areas. All you will observe is cessation of progression of symptoms. Know that Ca can be given via foliar application, too, which further allows you to push the EC of root feedings. With me so far?

You can do the same thing with Mg using MgSO4 at the rate of 1/4tsp/gal+surfactant (dish soap, JMS Stylet, aloe juice all work here).

What I do is alternate the supplements offered at feedings, one feed they'll get Ca (from the get-go, they're always getting it because it's immobile and is difficult to correct once onset is observed), the next they'll get their Mg.

Keep your Ca:Mg ratios at 3:1 or above.

As to using tap water to resolve any Ca or Mg problems, I personally was unable to do that because my (well) water, though very high in both Ca and Mg, had both minerals locked onto carbonates (the CO3 molecule). Carbonates affect pH, and they're difficult to break apart to make Ca and Mg available. It's available Ca and Mg that you're after here.

Was the coir charged with Ca or Cal-Mag, possibly + a light vegging solution, prior to planting? Obviously, this is brand-dependent, but I learned both by bein' tol' by a grownup and by making the mistake of not doing it well enough that it's rather important.

What else..? I've gotta think about it to get at what else, but right now you've got to resolve the Ca-. If you're late in flower (looking at around 2 weeks prior to choppy-chop) then it's a done deal, no need to spend time, money or energy on trying to resolve a problem that won't.

Wow, thanks for the great info. I will get a separate Ca only product. I haven't gotten into the castings or the teas yet. Will do some research on both. What sort of bennies are you doing your teas with?

If the problem is solved it will just not look any worse, correct?

This is Canna coir and has been used twice now. All pots were dumped out, roots hand picked out, then added 0.8 EC nutrient solution + zym and planted.
Throughout the veg the plants looked healthy, up until about a week before flip, I noticed they were pale. Originally I thought it was because of a bug spray he used.. Bug-B-Gone... I usually have my bugsprays @ a neutral pH, although this one got sprayed whatever RO water + Bug-B-Gone was... Do you keep your bug sprays neutral?
 
BCrocker

BCrocker

428
28
Something that directly affects nutrient takeup and is so often ignored I just suggest starting there; humidity. If your humidity levels changed (and as seasons change it is very likely to change the RH in your room) that could be a cause of your Ca problems.

Low humidity levels force plants to take up more moisture to compensate, which is why you run low values for nutes in dry climates. The opposite is also true and is easier to miss; when humidity climbs, your EC should climb with it, even as high as 2.4 with high humidity levels of 65% or more. When humidity climbs and EC doesn't, the plant will start to starve for nutes because it isn't bringing enough up with the water it's transpiring.

Ca is one of the worst offenders with this, because it's immobile and the affected leaves will not recover if all you do is change the nutes your roots see. Seamaiden's suggestion to foliar feed immobile nutrients is wise for this reason. When I sealed my room and could maintain humidity levels above 20% (!), I noticed my girls needed higher EC- and when they got it they really took off! To be specific, I added 5ml/gal of cal-mag in the dry, and 10 after the room was sealed. This was on top of whatever Ca the nutes had already. I'm in 50/50 coco/hydroton mix.

Another interesting point. The dehumid in this room was down all veg and the rh was 50 to 70.
 
Seamaiden

Seamaiden

Living dead girl
23,596
638
Wow, thanks for the great info. I will get a separate Ca only product. I haven't gotten into the castings or the teas yet. Will do some research on both. What sort of bennies are you doing your teas with?

If the problem is solved it will just not look any worse, correct?

This is Canna coir and has been used twice now. All pots were dumped out, roots hand picked out, then added 0.8 EC nutrient solution + zym and planted.
Throughout the veg the plants looked healthy, up until about a week before flip, I noticed they were pale. Originally I thought it was because of a bug spray he used.. Bug-B-Gone... I usually have my bugsprays @ a neutral pH, although this one got sprayed whatever RO water + Bug-B-Gone was... Do you keep your bug sprays neutral?
I don't usually use bug sprays, but whatever IPM I'm using (organic gal here) I only pH if it's stated in the directions.

I like to make teas from different plants, worm castings, or certain amendments/fertilizers (Dr. Earth, for example). Whatever I'm feeling at the moment, whatever looks as though it's growing really well, whatever I've just read about.
 
DowNwithDirT

DowNwithDirT

1,468
263
RO water needs extra calcium and magnesium (You removed them)
Canna needs extra calcium and magnesium(They rely on it being in your source water)
Coco needs extra calcium and magnesium (It has a high CEC and needs excess Ca, which has been proven to be immobilized in the coco)

You have been feeding god know what precipitate mess of calmag+. I would still recommend some gypsum and you should be using a minimum of 5 ml per gal of calmag, prob closer to 7.
 
NeverMrs

NeverMrs

20
3
Could his adding additional CalMG be causing an issue? It's a kush strain, but we are not sure exactly what. They seem to be growing quite different than the last batch. Btw, this is a 60/40 , coco/perlite mix.. I expect the soil pH to be coming out at around 6.0


So I have this theory... I could be totally out to lunch... I have similar issues, 4 grows in a row, tiny brown spots appear, then about a week later I see magnesium deficiencies pop up too. I believe that I'm overdosing CalMag, but so far haven't been able to test my theory because well, I have a boss... Ugh... Calcium and magnesium actually lock eachother out if you over do it. The coco we use is Urban Jardine, which is washed and buffered, I emailed them to find out what they use to buffer it... Guess what... They buffer with Calcium only! Fits in line with my theory... CalMag is added every water, and canna a and b already have higher amounts of both also, combine that with extra calcium in the coco and wham-o, I've successfully locked out both before they even flip to flower...

Hopefully you can test my theory... My hands are tied for now, but thought this might help. Now, depending on what coco you use, you may want to wash and buffer it yourself. Cocoforcannabis.com is an excellent website specific for coco growers and has great information on the process of buffering, but really, if you're seeing those brown spots in veg, cut the calmag before the magnesium gets locked out too otherwise the salt flats are going to be insane and you're wasting nutes... Remember that if you don't flush your plants at the end and the product smokes bad or tastes awful, you're using too many nutrients... The best growers are so precise, that they can harvest without flushing...
 
NeverMrs

NeverMrs

20
3
First thought is that it's really refreshing to see someone who actually knows what a Ca- looks like. That's my first thought.

Second thoughts are as follows: Get a separate Ca and Mg product. I like BioLink's 6% Ca, it's certified organic and doesn't give you extra N. Once I separated out Ca and Mg, I found everything went that much easier. Incorporating worm castings into the mix, as teas, top-dressings or part of your coir mix are quite helpful here as well, as can be good old molasses (it's part of my feeding regimen from start til end).

Allow pH to range a little more broadly, I feel that 5.8 is a bit tight and you'll see better uptake if you allow a range, easily up to 6.2, and ranges outside both ends, high and low, are also acceptable.

You will not observe any improvement in the already-affected areas. All you will observe is cessation of progression of symptoms. Know that Ca can be given via foliar application, too, which further allows you to push the EC of root feedings. With me so far?

You can do the same thing with Mg using MgSO4 at the rate of 1/4tsp/gal+surfactant (dish soap, JMS Stylet, aloe juice all work here).

What I do is alternate the supplements offered at feedings, one feed they'll get Ca (from the get-go, they're always getting it because it's immobile and is difficult to correct once onset is observed), the next they'll get their Mg.

Keep your Ca:Mg ratios at 3:1 or above.

As to using tap water to resolve any Ca or Mg problems, I personally was unable to do that because my (well) water, though very high in both Ca and Mg, had both minerals locked onto carbonates (the CO3 molecule). Carbonates affect pH, and they're difficult to break apart to make Ca and Mg available. It's available Ca and Mg that you're after here.

Was the coir charged with Ca or Cal-Mag, possibly + a light vegging solution, prior to planting? Obviously, this is brand-dependent, but I learned both by bein' tol' by a grownup and by making the mistake of not doing it well enough that it's rather important.

What else..? I've gotta think about it to get at what else, but right now you've got to resolve the Ca-. If you're late in flower (looking at around 2 weeks prior to choppy-chop) then it's a done deal, no need to spend time, money or energy on trying to resolve a problem that won't.


I like that you brought up buffering of the coco. I've worked with 2 "growers" that had no idea what I was talking about... conducting my own research, I later learned that the brand we use is buffered with calcium only, and that the calmag additive is more for the coco to hold on to than for the plants.
 
Terpz719

Terpz719

545
143
I like that you brought up buffering of the coco. I've worked with 2 "growers" that had no idea what I was talking about... conducting my own research, I later learned that the brand we use is buffered with calcium only, and that the calmag additive is more for the coco to hold on to than for the plants.
It's my understanding that coco, because of it's environment and possibly how it was washed, is loaded with sodium (bad for plants) and potassium. It has a higher affinity for Ca and Mg, so the buffering process displaces those elements with others that are more plant friendly. The fact that it's buffered with Ca only, I don't think is a problem. I think most folks who do buffer again at home use Cal/Mg because that's what they have handy, not that you have to buffer with both. FWIW, I haven't buffered my coco before use beyond whatever the supplier did.
 
TripsRabbit

TripsRabbit

1,259
163
So I have this theory... I could be totally out to lunch... I have similar issues, 4 grows in a row, tiny brown spots appear, then about a week later I see magnesium deficiencies pop up too. I believe that I'm overdosing CalMag, but so far haven't been able to test my theory because well, I have a boss... Ugh... Calcium and magnesium actually lock eachother out if you over do it. The coco we use is Urban Jardine, which is washed and buffered, I emailed them to find out what they use to buffer it... Guess what... They buffer with Calcium only! Fits in line with my theory... CalMag is added every water, and canna a and b already have higher amounts of both also, combine that with extra calcium in the coco and wham-o, I've successfully locked out both before they even flip to flower...

Hopefully you can test my theory... My hands are tied for now, but thought this might help. Now, depending on what coco you use, you may want to wash and buffer it yourself. Cocoforcannabis.com is an excellent website specific for coco growers and has great information on the process of buffering, but really, if you're seeing those brown spots in veg, cut the calmag before the magnesium gets locked out too otherwise the salt flats are going to be insane and you're wasting nutes... Remember that if you don't flush your plants at the end and the product smokes bad or tastes awful, you're using too many nutrients... The best growers are so precise, that they can harvest without flushing...
I just mix in some garden gypsum before potting with coco. I use no exact amount, about a solo cup full for 5kg block of coco. This adds calcium and sulphur to the coco before you start growing in it. You can then add more to the top of the coco when the plant is a teen and when it starts to flower. You can also add magnesium with epsom salts. This way you can tweak the cal and mag amounts and control the calmag lockout you're talking about.
 
NeverMrs

NeverMrs

20
3
It's my understanding that coco, because of it's environment and possibly how it was washed, is loaded with sodium (bad for plants) and potassium. It has a higher affinity for Ca and Mg, so the buffering process displaces those elements with others that are more plant friendly. The fact that it's buffered with Ca only, I don't think is a problem. I think most folks who do buffer again at home use Cal/Mg because that's what they have handy, not that you have to buffer with both. FWIW, I haven't buffered my coco before use beyond whatever the supplier did.


That's precisely it... it's called cation exchange, calcium and magnesium bond to the coco more readily than potassium, and prevent the roots from getting any... A bit greedy I guess... So if it's already buffered then that would suggest that we don't need to add much, as the calmag would already be available to the plants, although possible that the magnesium is slightly higher or less than the bond of calcium, but I'm not a chemist... Basically I think I should scrap the calmag altogether and MAYBE increase my a and b a bit, which apparently already has double the percentage calmag as my additive...
 

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